Expandable dental impression tray

Abstract

A dental impression tray is made of thermoplastic material which may be heated in order to shape the tray to accommodate the patient's dental arch. The tray includes a channel for receiving impression material, and the channel has a folded section which may be unfolded when the tray is heated in order to increase the height, width or length of the channel. The folded section extends outwardly from the channel and provides convenient gripping structure for removing the tray from the mouth after the impression is taken.

We claim: 
     
       1. A dental impression tray having an elongated impression channel adapted to receive a quantity of impression material, said tray comprised of a thermoplastic material malleable at elevated temperatures, said channel including a buccal side, a lingual side facing said buccal side and an occlusal side between said lingual side and said buccal side, said buccal side, said lingual side and said occlusal side adapted to extend about buccal, occlusal and lingual regions respectively of at least a portion of an alveolar ridge, at lest one of said lingual side, said buccal side and said occlusal side including an outwardly extending folded section that may be partially unfolded when said channel is heated to elevated temperatures to an orientation directly facing the alveolar ridge in order to enlarge the size of said impression channel and extend said channel further about the alveolar ridge. 
     
     
       2. The tray according to claim 1, wherein said folded section extends in an occlusal plane substantially parallel to said occlusal side. 
     
     
       3. The tray according to claim 2, wherein said folded section is directly connected to said buccal side of said channel. 
     
     
       4. The tray according to claim 3, wherein said folded section includes an occlusal portion substantially coplanar with said occlusal side of said channel. 
     
     
       5. The tray according to claim 1, wherein said folded section extends substantially the entire length of said channel. 
     
     
       6. The tray according to claim 1, wherein said tray is generally U-shaped in plan view, and wherein said folded section extends substantially along the entire perimeter of said channel. 
     
     
       7. The tray according to claim 1, wherein said folded section extends in a direction substantially perpendicular to the longitudinal axis of said channel. 
     
     
       8. The tray according to claim 7, wherein said folded section extends along substantially the entire extent of said buccal side, said occlusal side and said lingual side. 
     
     
       9. The tray according to claim 7, wherein said tray has a posterior portion, and wherein said folded section is located in said posterior portion. 
     
     
       10. The tray according to claim 1, wherein said tray has a substantially U-shaped configuration in plan view, and wherein said folded section extends substantially along the length of said channel; and including a second folded section extending in a direction substantially perpendicular to the longitudinal axis of said channel.